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为探究煤粉添加半焦后混合燃料的燃烧性能,通过热重分析研究煤、半焦及其混合物的燃烧过程,得到燃烧特性参数.由于不同温度区间的燃烧反应机理不同,利用分段法对燃烧过程进行动力学分析,对燃烧反应的前、后期分别使用缩核反应模型和缩核内扩散模型进行模拟,从而得到动力学参数.结果显示,随着混合燃料中半焦含量增加,其可燃性指数和燃烧特性指数都减少,燃烧前期活化能由76.79 k J·mol~(-1)增加到92.75 k J·mol~(-1),后期活化能由102.62 k J·mol~(-1)增加到107.94k J·mol~(-1),说明半焦的添加会降低混合燃料的燃烧性能.对比不同半焦含量的混合燃料的燃烧特性参数和动力学参数,半焦的质量分数应控制在15%以内最适宜.
In order to investigate the combustion characteristics of the mixed fuel after the pulverized coal was added, the combustion characteristics of coal, semi-coke and their mixtures were studied by TG analysis, and the combustion parameters were obtained.Because of the different combustion reaction mechanism in different temperature ranges, The kinetics of the combustion process was analyzed, and the kinetic parameters were obtained by using the model of the nucleation reaction and the model of the diffusion-nucleus diffusion respectively before and after the combustion reaction.The results showed that with the increase of the semi-coke content in the mixed fuel, the flammability The activation energy of pre-combustion increased from 76.79 kJ · mol -1 to 92.75 kJ · mol -1, and the post-combustion activation energy decreased from 102.62 kJ · mol -1, To 107.94k J · mol -1, indicating that the addition of semi-coke will reduce the combustion performance of the mixed fuel.Comparing the combustion characteristics and kinetic parameters of the mixed fuel with different semi-coke content, the semi-coke mass fraction should be controlled Within 15% of the most appropriate.